Collapsible metal core for molding concrete



Jan. 29, 1946;

(1 \AL (5ll.LJl\hd COLLAPSIBLE METAL GORE FOR MOLDING CONCRETE 2Sheets-Sheet 1 Filed May 5, 1945 Tali Jan.29,1946. v "c. WQGILUAJ2,393,765

COLLAPSIBLE METAL CORE FOR MQLDiNG' CONCRETE Filed May 5, 1945 2Shets-Sh ee t 2 Patented Jan. 29, 1946 COLLAPSIBLE METAL com; FOR

. CONCRETE MOLD ,G,

Coleman W. Gilliam, Birmingham, Aia., assignor of one-third to Perry J.Coyle and one-third to E. Y. McMorries, Birmingham, Ala.

Application May 5, 1945, Serial No. 592,195

3 Claims.

This invention relates to a collapsible metal concrete core, and has forits main object to provide such a core that will be highly efficient tocast hollow spaces in concrete slabs, floors, or walls of any size spacedesired. The present invention is very simple in construction as compared to complicated devices that have heretofore been made that werenot practical for the Purpose intended. Other advantages will appearfrom the description.

The use of hollow concrete for building purposes is on the increase, anda simple efiicient collapsible core like the present invention isessential to hold down excessive costs.

By referring to the drawings, part of this application, it will beobserved that Fig. l is a general isometric view of the assembled corepartly cut away; Fig. 2 is an enlarged cross sectional view of theassembled core; Fig. 3 is a longitudinal sectional view of the core inconcrete featuring the retaining wedges; Fig. 4 is a cross sectionalview of the core in concrete; Fig. 5 is an exploded view of the core.

Similar reference numerals refer to similar parts throughout the severalviews.

Again referring to the drawings in detail it will be seen that thedevice comprises two flat plates I and 2 with bent inward edges I I forstif- ,fening the plates. The sides are made in sections 3, 4, 5 and 6somewhat L shaped with reverting edges 9 and I adapted to hook into eachother and thus form a joint along the middle of each side of theassembled core. The wedges I and 8 are made substantially the length ofthe main plates with open edge I4 adapted to rest against the mainplates when assembled with the closed edges l2 and I3 adapted to fit inpairs against each other to form long tapering wedges. These wedges aresimilar and any number of pairs may be used in the assembly but thedrawings show three pairs.

Figure is an exploded view of parts of the core in their unattached butindicated attached position. To assemble the core for use the ends 4 and6 of the side parts are placed under the bent edges II of the plate 2;then the wedges I are laid lengthwise upon the plate 2; then the sidesections are connected at the lapping joints 9 and I0; then thecompanion wedges 8 are placedover the other wedges but not fully face toface; then the top plate I is put in place over the assembled wedges andwith the top ends 3 and 5 of the side section placed over the bent edgesof the top plate; then the wedge are driven tight to hold the assembledcore together. Or

the core may be assembled in any other convenient manner as determinedby the user.

The core is constructed of heavy gauge metal, preferably galvanizediron. But any other suitable material may be used for the purpose.

From the foregoing it will appear that the assembled core is held andlocked together by the long V shaped wedges. Thewedges not only lock allpieces together but also act as supports for the weight of the concrete.To remove the core thewedges are released by separation and pulled outof the core, then the plates are free to be removed. With the wedges andplates out of the way, the side sections can be removed by looseningtheir joints and sliding the coinpanion side parts together.

When placing the core into the form for the pouring of concrete it isdesirable to either oil or grease the core or cover it with suitablepaper so as it can be easily removed from the concrete.

While I have shown and described the preferred embodiment of myinvention, I do not wishto limit same to the exact and precise detailsof structure, but reserve the right to make all modifications andchanges so long as I remain within the spirit and scope of the followingclaims.

Having described my invention I claim: 1. A collapsible metal concretecore comprising, two main plates, two opposite edges on each of saidplates bent downward and inward to form a V shape for stiffening saidplates, a two piece channel as each side member of said core, each ofsaid channel members having an overlapping portion to form a jointcoextensive with said members and centrally located when two of saidmembers are joined, a plurality of gradually tapering wedges positionedbetween said plates, the flange portions of said channel side membersoverlapping the V bent edges of said plates, said wedges adapted whendriven in tight to press the bent edges of said plates against the innerfaces of the edges of the flanges of said channel side members.

2. A device of th character described comprising, two main platespositioned opposite each other, two opposite edges of each plate beingbent downward and inward V shaped fo stiffening said plates, two pairsof channel shaped members as sides of said core, each of said pairs ofsaid channel shaped members having lapped over edges adapted to hookinto each other and form a joint, a plurality of pairs of graduallytapering wedges, each of said pairs of wedges adapted to fit face toface and expand by movement; said pairs of wedges adapted to fit betweensaid plates and press the bent edges of said plates against the flangeportions of said channel members.

3. 'A' collapsible metal concrete core of the character describedcomprising two main plates of 'substantially'equal size eachof saidplates having two of its opposite edges bent downward and. inward toform V shaped edges, two pairs of partially L shaped side memberscoextensive in length with said plates, each of said L shaped membershaving a bent over and upon itself portion adapted to fit one into theother to forms" detachable joint for holding a pair of said sidepieces'together, said pair when thus joined forming a channel member,the flange portion of each of said pairs adapted to fit over the Vshaped edges of said plates and thus form a four wall enclosure; aplurality of pairsof gradually tapering wedges adapted to fit into saidenclosure beof said plates against the inner faces of the flange platesand sides firmly but 'detachably together. i COLEMAN W. GILLIAM;

